76 Chapter IV 



accuracy of this thesis. In spite of this uncertainty, it may be 

 accepted as fully demonstrated, that certain fixed amoeboid cells, 

 such as the large elements of the splenic pulp, of the lymphatic 

 glands, and of the omentum, play an important part in the resorption 

 of cells. It is there that elements filled with red corpuscles and 

 white corpuscles in process of being destroyed are so often found. 

 Just as certain fixed cells do not function as true phagocytes, 

 so also in some leucocytes this function is undoubtedly absent. The 

 suggestion has been made several times that any cell element, 

 provided it be young, is capable of ingesting foreign bodies. The 

 examination of white corpuscles proves exactly the contrary. The 

 smaller white corpuscles found in fairly large numbers in the blood 

 and the lymph, and which are commonly known as lymphocytes or 

 small lymphocytes, are simply leucocytes with very little protoplasm 

 which in this state never fulfil phagocytic functions. It is only when it 

 becomes older, when its nucleus, single and rich in chromatin, becomes 

 surrounded by an ample layer of protoplasm, that the lymphocyte 

 becomes capable of ingesting and resorbing foreign bodies. Several 

 [82] authors, with Ehrlich at their head, still assign to these larger cells 

 the same name — lymphocytes. Others, however, give them the name 

 of large mononuclear cells. Confusion is thus possible, especially as 

 Ehrlich includes under the same term the large mononucleated leuco- 

 cyte, a very rare form of cell in human blood, which is distinguished 

 by the greater staining capacity of its nucleus. To avoid this incon- 

 venience I propose to designate the large lymphocytes by the name 

 of blood macrophages and lymph macrophages {haemomacrophages, 

 lymphomacrophages). This term is preferable to that of mononuclear 

 leucocytes, especially as in exudations we frequently meet with macro- 

 phages with two and even several sharply separated nuclei. Giant cells, 

 moreover, are nothing but polynucleated macrophages. On the other 

 hand, the leucocytes so often designated by the name of polynuclear in 

 reality contain but a single nucleus. Even Ehrlich, who introduced this 

 term, acknowledged its imperfection but he retained it for some time 

 because it was already very extensively used and could, he thought, 

 give rise to no misunderstanding. In his excellent work on anaemia, 

 published jointly with Lazarus^, he now agrees that the name of " cells 

 with polymorphous nuclei " would be more exact. 



^ Ehrlich u. Lazarus, "Die Anaemie," in Nothnagel's "Specielle Pathologie u. 

 Therapie," Wien, 1898, Bd. viii, l^er Theil, S. 49. Cf. the authorised English trans- 

 lation, "Histology of the Blood," Cambridge, 1900, p. 74. 



